Lighting Wavelengths
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fijiblue
Active member
Im just curious as to where this is cited. I've read journals in which it was explained that when plants received primarily blue light, their protein production increased (nearly doubled) and their carbohydrate production decreased. That was left out in Bean's initial post, but later was somewhat touched on with the statement that more red spectrum would equal more growth (carbohydrate) and more blue light equals more color (protein).
From the journals I read, however, I understood that it was based on spectral quality. Higher amounts of red light (low spectral quality)were not as useful, but since they are in a higher energy (PAR) and overpowering, the coral can reach saturation levels. On the opposite end, blue light is much more of an efficient spectrum and the coral would need less to accomplish the same thing. Maybe I need to go back and reread this topic again
Of course every time I ask Dana Riddle this he tells me the same thing that a photon is a photon regardless of color origin.
From the journals I read, however, I understood that it was based on spectral quality. Higher amounts of red light (low spectral quality)were not as useful, but since they are in a higher energy (PAR) and overpowering, the coral can reach saturation levels. On the opposite end, blue light is much more of an efficient spectrum and the coral would need less to accomplish the same thing. Maybe I need to go back and reread this topic again
Of course every time I ask Dana Riddle this he tells me the same thing that a photon is a photon regardless of color origin.
greenbean36191
Premium Member
This is an example of common knowledge. Aside from citing a physics book about EM waves and biochem book on photosynthesis I can't help a whole lot here.
The Stark-Einstein law tells you that for each photon you get one quantum of photochemical energy. You don't get partially excited or super-excited electrons or multiple electron excitations per photon. Any energy lost in the transfer goes into heat or in the case of photosynthesis, fluorescence. It's important to note here that we aren't talking about the fluorescence that gives corals pretty colors. You mostly get red fluorescence, just like in green plants. Unless you're looking with special filters, you're not going to see it. The pretty colors are from fluorescent proteins in the corals themselves that don't really have much to do with photosynthesis. That's a whole different subject.
The 2x value is just a rough approximation based on action spectra, but none in particular. It's pretty arbitrary. The wasted energy goes back to the E=hc/lambda formula zimster brought up. I apparently calculated the percent change backwards though (I calculated as if a red photon was increasing in energy to be equivalent to a blue), so the blue photon is actually only wasting 43% of its energy, not 75%. Still, you end up roughly at a wash, especially if you factor in inefficiency in transfers from antennae to reaction centers.
greenbean36191
Premium Member
I'd have to see the context and what was actually measured here, but photosynthesis produces carbs, not protein. Any light induced changes in protein would most likely be due to changes in the concentrations of proteins that regulate photosynthesis. This wouldn't be indicative of increased growth, just a redistribution of resources.
Well, they aren't higher in energy, but that doesn't really mater for photosynthesis. Basically this is the case. You're producing lots more photons and still catching a high percentage of them and once they're captured, almost all of their energy goes into photochemistry.
Well it depends how you measure efficiency. It is more efficient in the percentage of photons that are captured as compared to red light. However, it's much less efficient in the percentage of the energy of those photons that actually goes into photochemistry.
Again though I think you understand the basic concept. One thing that's illustrated by activity spectra is the relative amounts of a given spectrum it would take to reach saturation. If the red peak is at 75% of the blue peak, it would take about 25% more red light to reach saturation as compared to blue light.
Zimster
Member
I am curious as to how to find these values... ^
Once a photon is made, it cannot change in energy unless it changes wavelength. This is proven by that E=hc/lambda formula. all this formula tells someone is the number of joules a photon of a given wavelength has.
The stark-einstein law states that dE=Nhc/lambda, and N is the number of atoms in a mol. With this law it shows that about 20.7% more energy/mol is created with a blue photon (460nm) than created with a red one (700nm) when considering photochemistry. This would indicate that blue light gives more energy per photon than red light does with more photons. Since it would take 25% more light to reach saturation in the red end of the spectrum, and 20.7% more energy is obtained with blue light than red light, when the same amount of light in the whole spectrum is given to the coral, it uses the blue light more effectively. In other words, you could have 400 watts of 6700K-10000K and achieve the same level of happiness for the coral as you can with 217.24 watts of blue light, right?
Why is it that a single photon of any color can produce the same amount of energy as any other of any wavelength for coral when the stark-einstein law states otherwise? I know there is energy loss due to heat and fluorescence but isn't this due to saturation also?
greenbean36191
Premium Member
I got the 43% value from the percent change in energy of a 400nm photon losing its energy to be equivalent to a 700nm photon. If I screwed up the percent change equation there's a good chance I mixed up units in there too, so you might want to check.
The only part of Stark-Einstein's law that's relevant to photosynthesis is that one photon excites one electron. How much it excites that electron is irrelevant to how much sugar is eventually made. The reason is that photosynthesis is a long pathway of reactions. All that initial excited electron does is kick off the next reaction in the series. In order to do that it just has to reach a certain energy threshold (equivalent to the energy from a red photon). The next reaction can only be set off once per excited electron, so any energy above that threshold is lost.
The only part of Stark-Einstein's law that's relevant to photosynthesis is that one photon excites one electron. How much it excites that electron is irrelevant to how much sugar is eventually made. The reason is that photosynthesis is a long pathway of reactions. All that initial excited electron does is kick off the next reaction in the series. In order to do that it just has to reach a certain energy threshold (equivalent to the energy from a red photon). The next reaction can only be set off once per excited electron, so any energy above that threshold is lost.
Saturation just means that you've reached the point where photosynthesis is running as fast as it can. The efficiency of photosynthesis doesn't change, it just can't go any faster, so increasing intensity further has no effect on production.
Zimster
Member
I see....thanks for your clarification greenbean.....
I looked back at my calculations and they are incorrect because i forgot about the energy to create each photon and i was only looking at the power. A 400 watt bulb (initially lets say that it only outputs 670nm light) over a given area produces 1.3482*10^21 photons per sec. In order to achieve this number of photons for blue light (strictly 460nm), a 582.61 Watt bulb would be needed. Since a red photon and a blue photon produce the same amount of sugar when they change into an electron, the 20.7% more energy of the blue photon does not matter. Since blue light is used 25% better than red light, we can subtract this amount from the total power. This yields 436.96 watts.
I looked back at my calculations and they are incorrect because i forgot about the energy to create each photon and i was only looking at the power. A 400 watt bulb (initially lets say that it only outputs 670nm light) over a given area produces 1.3482*10^21 photons per sec. In order to achieve this number of photons for blue light (strictly 460nm), a 582.61 Watt bulb would be needed. Since a red photon and a blue photon produce the same amount of sugar when they change into an electron, the 20.7% more energy of the blue photon does not matter. Since blue light is used 25% better than red light, we can subtract this amount from the total power. This yields 436.96 watts.
In light of the above discussion, Chromatinet shadecloth is utilized by Coral Greenhouse growers
Chromatinet is a very different product it is a narrow spectrum shadecloth and absorbs most of the upper wavelengths (yellow to red) which helps quite a bit with heat reduction. it also makes sure that the highest amount of blue spectrum gets through thereby producing an effect similar to Actinic Lighting (although not quite low enough in the spectrum to be true actinic).
http://www.chromatinet.com/
How does this jive?
Chromatinet is a very different product it is a narrow spectrum shadecloth and absorbs most of the upper wavelengths (yellow to red) which helps quite a bit with heat reduction. it also makes sure that the highest amount of blue spectrum gets through thereby producing an effect similar to Actinic Lighting (although not quite low enough in the spectrum to be true actinic).
http://www.chromatinet.com/
How does this jive?
Everyones Hero
New member
So to determine which bulb would be best for a particular application you'd have to consider how deep the tank was, as well as how many photons of light are produced in a given time, as well as loss from reflection & through the water (refraction?).
Number of photons produced - reflected photons - photon loss through water = usable photons
I might have to get a PAR meter when I get my new bulbs. It'll give me a chance to see how much usable light each bulb is putting into my tank, & see which ones will benefit the tank more.
I'm going to hypothesize that:
Blue light may travel better through water, but since our tanks aren't that deep (compared to the ocean) it may be more beneficial to use more red since there are more photons being produced & the loss won't be as great as the loss through deeper waters.
I'd like to do an experiment, but I don't have the money:
-2 identical tanks
-4 frags each from the same mother colony. 2 high in the tank, 2 low in the tank
-Same directed flow
-2 T5 lights on each. 2 lights covering the Violet-Green spectrum on one tank & on the other 2 lights covering the Yellow-Red spectrum.
Set the tanks up to share water so the water parameters are the same. Same type & number of powerheads, setup the exact same way. Since the only variable would be the light spectrum you could see which would be best for growth.
Record the amount of growth of all 8 frags. Red might turn out to be better for corals higher up while blue is better for corals on the bottom.
After the experiment view all 8 frags under a full spectrum of lights (acintics, daylight, 10k, 6500) and compare the colors. If the corals growing under the Yellow-Red spectrum have a color deficiency you would know that the blue is necessary for corals to keep their color. If not you could use more lower K lights for growth & use fewer higher K bulbs just for astetic purposes.
Number of photons produced - reflected photons - photon loss through water = usable photons
I might have to get a PAR meter when I get my new bulbs. It'll give me a chance to see how much usable light each bulb is putting into my tank, & see which ones will benefit the tank more.
I'm going to hypothesize that:
Blue light may travel better through water, but since our tanks aren't that deep (compared to the ocean) it may be more beneficial to use more red since there are more photons being produced & the loss won't be as great as the loss through deeper waters.
I'd like to do an experiment, but I don't have the money:
-2 identical tanks
-4 frags each from the same mother colony. 2 high in the tank, 2 low in the tank
-Same directed flow
-2 T5 lights on each. 2 lights covering the Violet-Green spectrum on one tank & on the other 2 lights covering the Yellow-Red spectrum.
Set the tanks up to share water so the water parameters are the same. Same type & number of powerheads, setup the exact same way. Since the only variable would be the light spectrum you could see which would be best for growth.
Record the amount of growth of all 8 frags. Red might turn out to be better for corals higher up while blue is better for corals on the bottom.
After the experiment view all 8 frags under a full spectrum of lights (acintics, daylight, 10k, 6500) and compare the colors. If the corals growing under the Yellow-Red spectrum have a color deficiency you would know that the blue is necessary for corals to keep their color. If not you could use more lower K lights for growth & use fewer higher K bulbs just for astetic purposes.
hahnmeister
In Memoriam
You are correct that red light is filtered out very quickly in saltwater, which is rather amazing since the spectral graph of light above the water is almost a horizontal flip of the light field at just one meter of water depth (much different intensity of course). Most corals beyond 5m dont have much use for it either because, well... why require/benefit from something that you aren't likely to get anyways? It would be as if humans discovered one day that eating plastic should be part of our daily diet... very unlikely considering plastic didn't exist in our evolution until the last few decades. Many deepwater corals actually use red pigments as camo... since fish cant see red in theory, and even for us, red under blue light just looks black.
That being said, there have been tests with red LED's and SPS, where the red light was shown to photoinhibit the corals at lower levels than blue light... which is odd since red light contains less energy... still, small spikes in the red wavelength could be a trigger (not in their power, but if the coral can sense/see the spectrum) for more pigments since in the wild, if the coral were being exposed to red light, it would mean it is in some very shallow water, and could use the extra pigmentation to sheild it from too much light. Clams do this... so why not corals?
And, there are people who use supplimental 'red spike' T5's... like the ATI pro-color and KZ fiji purple. These bulbs have a very deep red spike... almost too red for us to see well. Some people also add one 3000K bulb to a T5 array to boost the yellow/green spectrums. Without them, those same people reported that their pink/red/yellow corals were less intense and faded under the otherwise blue dominated spectrums that most T5's put out (some green, but mostly blue). I have had red, pink, and yellow corals pigment in very well just under aquablue, actinic+, and actinic03 bulbs though (better than halide). So I dont know how much stock I would put in those findings. I think that the results often depend on the light intensity as well as spectrum... so lack of intensity could be made up for with certain spectrums to 'fool' the coral into thinking its in shallower water. Maybe... its a long shot, but I could see it. Your light intensity with the T5's might not be as great, so your corals start to fade and turn pastel colors, so you add some 'warmer spectrums' to the mix and the corals think they are getting warmer spectrum/higher intensity light like in nature where spectrum and intensity are related. Our eyes actually work in a similar way with response to spectrum and intensity.
http://www.advancedaquarist.com/2005/8/aafeature/view?searchterm=iwasaki
Some corals, like Xenia, dont care... you can grow them under sodium bulbs, or actinics... they adapt to whatever spectrum you give them and their growth is only relative to intensity, not spectrum. So it seems different corals have different 'ideal spectrums'... which makes sense... if you were a deepwater coral, you would likely adapt to only use bluer light. If you were a coral that liked shallower water, you most likely use more warm spectrums and green. If you are a coral that spreads like a weed, and needs to adapt to whatever happens to be where you are going (Xenia), then you must have to adapt to all sorts of spectrums. Heck, there are Xenia that are exposed to air throughout the day due to low tide, so their spectrum goes from being blue dominant to being green and red dominant... so being able to adapt to such a warm source of light is a good idea. Some deeper water species, even ones at just 5m, may not be able to adapt to that spectrum at all.
Ill admit that my T5 setups have always been an even match wattage wise with what a halide system would be (some go for much lower wattage), so my light levels under T5's are much higher, and this is likely why my reds/oranges/yellows/pinks are more intense under T5's than halides, if nothing else... and the spectrums I use lack red all together.
That being said, there have been tests with red LED's and SPS, where the red light was shown to photoinhibit the corals at lower levels than blue light... which is odd since red light contains less energy... still, small spikes in the red wavelength could be a trigger (not in their power, but if the coral can sense/see the spectrum) for more pigments since in the wild, if the coral were being exposed to red light, it would mean it is in some very shallow water, and could use the extra pigmentation to sheild it from too much light. Clams do this... so why not corals?
And, there are people who use supplimental 'red spike' T5's... like the ATI pro-color and KZ fiji purple. These bulbs have a very deep red spike... almost too red for us to see well. Some people also add one 3000K bulb to a T5 array to boost the yellow/green spectrums. Without them, those same people reported that their pink/red/yellow corals were less intense and faded under the otherwise blue dominated spectrums that most T5's put out (some green, but mostly blue). I have had red, pink, and yellow corals pigment in very well just under aquablue, actinic+, and actinic03 bulbs though (better than halide). So I dont know how much stock I would put in those findings. I think that the results often depend on the light intensity as well as spectrum... so lack of intensity could be made up for with certain spectrums to 'fool' the coral into thinking its in shallower water. Maybe... its a long shot, but I could see it. Your light intensity with the T5's might not be as great, so your corals start to fade and turn pastel colors, so you add some 'warmer spectrums' to the mix and the corals think they are getting warmer spectrum/higher intensity light like in nature where spectrum and intensity are related. Our eyes actually work in a similar way with response to spectrum and intensity.
http://www.advancedaquarist.com/2005/8/aafeature/view?searchterm=iwasaki
Some corals, like Xenia, dont care... you can grow them under sodium bulbs, or actinics... they adapt to whatever spectrum you give them and their growth is only relative to intensity, not spectrum. So it seems different corals have different 'ideal spectrums'... which makes sense... if you were a deepwater coral, you would likely adapt to only use bluer light. If you were a coral that liked shallower water, you most likely use more warm spectrums and green. If you are a coral that spreads like a weed, and needs to adapt to whatever happens to be where you are going (Xenia), then you must have to adapt to all sorts of spectrums. Heck, there are Xenia that are exposed to air throughout the day due to low tide, so their spectrum goes from being blue dominant to being green and red dominant... so being able to adapt to such a warm source of light is a good idea. Some deeper water species, even ones at just 5m, may not be able to adapt to that spectrum at all.
Ill admit that my T5 setups have always been an even match wattage wise with what a halide system would be (some go for much lower wattage), so my light levels under T5's are much higher, and this is likely why my reds/oranges/yellows/pinks are more intense under T5's than halides, if nothing else... and the spectrums I use lack red all together.
hahnmeister
In Memoriam
A photon of light is a photon of light... so the PAR/PPFD of one photon crossing a barrier to measure it (a par meter) will register the same number for green as it would blue, as well as red. So its not that yellow/green produce more par than blue really. In fact, blue light, being of higher frequency, contains more power than red, and green contains more than red but less than blue.
As it turns out, this explains a good deal why it just so happens that bulbs have a harder time making blue than warmer spectrums. Is that what you meant?
Blue wavelengths take more energy to create because of their higher frequency, so if you have 500 watts of blue light and 500 watts of yellow light.... chances are that the blue light just wont be able to make as many photons.
It also depends on the bulb itself. Some bulb technologies are better at different spectrums. Fluorescent lamps have a core that is mostly UV (ever seen a clear tube bulb.?.. its a UV-C lamp) at the center the bulb has already converted as much as it can to very high wavelengths, and then the phosphors convert this to the visible light we see... but because the core of the bulb is already at one end... converting to blue and actinic is alot easier than say... red. This also has a good deal to do with the phosphors. The elements used to make phosphors to produce blue are very stable, durable, and efficient. But the ones used to produce actinic... not so much. So thats just 'pick & choose'... different bulbs have the ability to make light very well at different peaks, so its not just a 'blue light is harder to make than red'... because LED's for instance... the blue wavelengths are perhaps the strongest output for them. Halides are similar... they follow the same general rule that blue light is harder to make than warmer spectrums (or green is harder than yellow, etc), but it all comes down to the halides in the bulb after all. Its not as if we are anywhere near 'high efficiency' when it comes to lighting. A 400 watt halide, even a 3000K, is making only 100 watts of actual light at best... 75% of that is going directly to heat. So there is the possibility that some new halide mix, or new bulb technology will just provide some new way of exciting an atom into making even more light... there is plenty of room for improvement. That light source might be super efficient at making green light say... but have a very hard time making blue or red. Just like using a spectrometer to ID an element/compound. But in general... blue light is harder to make, so thats why a 'full spectrum' bulb tends to drop in output when it goes from 3000K to 20,000K. But you never know... someone might come along and invent a gas that makes tons and tons of actinic... and then that would change. The demand on the market for lighting that makes light in this spectrum is rather low though... most advances are in the warmer spectrums that are used more commonly than with reef tanks... so dont hold your breath.
One example of what could be awesome for reef keepers is a sulphur-plasma vapor/induction bulb. If a magnetron (like what runs a microwave) were developed at a high enough frequency and focus to make them cooler and more compact (they tend to be 1400 watts at a minimum, need an active fan system for cooling because they run hot enough to melt their own glass, and need to be spun on their mount like food in a microwave so the energy doesn't burn a hole in one spot on the glass either)... they would be awesome. They have an efficiency which is about 50% better than your best halides can hope to be, and they do this at a natural spectrum of about 10,000K. The lighting industry sees this as a drawback since most light applications so not favor a 10,000K bulb... so it may never come to be. Making plasma bulbs is sooo cheap its not funny (you could DIY one if you wanted)... that might be another reason why nobody wants to make them...lol. Without any electrodes in the bulb either (all power is inducted), they can be made to last very long, like LED's... no doubt a drawback for someone trying to sell bulbs. The aquarium market is a small one, but we buy bulbs every year while most other applications leave the bulbs until they burn out. So making a bulb that could last 10 years in this market could be seen as a good way to kill the market all together, esp considering how cheap the bulbs would be to produce.
As it turns out, this explains a good deal why it just so happens that bulbs have a harder time making blue than warmer spectrums. Is that what you meant?
Blue wavelengths take more energy to create because of their higher frequency, so if you have 500 watts of blue light and 500 watts of yellow light.... chances are that the blue light just wont be able to make as many photons.
It also depends on the bulb itself. Some bulb technologies are better at different spectrums. Fluorescent lamps have a core that is mostly UV (ever seen a clear tube bulb.?.. its a UV-C lamp) at the center the bulb has already converted as much as it can to very high wavelengths, and then the phosphors convert this to the visible light we see... but because the core of the bulb is already at one end... converting to blue and actinic is alot easier than say... red. This also has a good deal to do with the phosphors. The elements used to make phosphors to produce blue are very stable, durable, and efficient. But the ones used to produce actinic... not so much. So thats just 'pick & choose'... different bulbs have the ability to make light very well at different peaks, so its not just a 'blue light is harder to make than red'... because LED's for instance... the blue wavelengths are perhaps the strongest output for them. Halides are similar... they follow the same general rule that blue light is harder to make than warmer spectrums (or green is harder than yellow, etc), but it all comes down to the halides in the bulb after all. Its not as if we are anywhere near 'high efficiency' when it comes to lighting. A 400 watt halide, even a 3000K, is making only 100 watts of actual light at best... 75% of that is going directly to heat. So there is the possibility that some new halide mix, or new bulb technology will just provide some new way of exciting an atom into making even more light... there is plenty of room for improvement. That light source might be super efficient at making green light say... but have a very hard time making blue or red. Just like using a spectrometer to ID an element/compound. But in general... blue light is harder to make, so thats why a 'full spectrum' bulb tends to drop in output when it goes from 3000K to 20,000K. But you never know... someone might come along and invent a gas that makes tons and tons of actinic... and then that would change. The demand on the market for lighting that makes light in this spectrum is rather low though... most advances are in the warmer spectrums that are used more commonly than with reef tanks... so dont hold your breath.
One example of what could be awesome for reef keepers is a sulphur-plasma vapor/induction bulb. If a magnetron (like what runs a microwave) were developed at a high enough frequency and focus to make them cooler and more compact (they tend to be 1400 watts at a minimum, need an active fan system for cooling because they run hot enough to melt their own glass, and need to be spun on their mount like food in a microwave so the energy doesn't burn a hole in one spot on the glass either)... they would be awesome. They have an efficiency which is about 50% better than your best halides can hope to be, and they do this at a natural spectrum of about 10,000K. The lighting industry sees this as a drawback since most light applications so not favor a 10,000K bulb... so it may never come to be. Making plasma bulbs is sooo cheap its not funny (you could DIY one if you wanted)... that might be another reason why nobody wants to make them...lol. Without any electrodes in the bulb either (all power is inducted), they can be made to last very long, like LED's... no doubt a drawback for someone trying to sell bulbs. The aquarium market is a small one, but we buy bulbs every year while most other applications leave the bulbs until they burn out. So making a bulb that could last 10 years in this market could be seen as a good way to kill the market all together, esp considering how cheap the bulbs would be to produce.
Thanks Hahnmiester. sorry but i still have one question. Say for example i have an ATI blue plus and an aquablue. The aquablue puts out more but the blue plus has a greater peak in the blue stectrum. why does it have more par?
Of a different note, do you have any threads regarding your T5 reflector testing or any other t5 threads you have. Im currently using IC SLR retro but wanding if it would be worth upgrading to ATI reflectors (if i can find them)
thanks
Aaron
Of a different note, do you have any threads regarding your T5 reflector testing or any other t5 threads you have. Im currently using IC SLR retro but wanding if it would be worth upgrading to ATI reflectors (if i can find them)
thanks
Aaron
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Todd March
Premium Member
I've always thought of the red spike in newer bulbs, particularly in the Fiji Purple (which has an actinic/blue spike also that makes it fluroesce GFP's very well) as tailored made for the blue and red photosynthesis peaks in chlorophyll "a"... Though since we can't see spectral graphs for either the Fiji or the Pro Color, who knows how close they actually are to 665 nm...
Although I think your theory of fooling the corals into producing more pigment, thinking they are in shallower water, is very interesting, Hahn...
Although I think your theory of fooling the corals into producing more pigment, thinking they are in shallower water, is very interesting, Hahn...
hahnmeister
In Memoriam
Nothing published yet... Im waiting on a straggler. Based on what I have seen though, if you are using the Icecaps, I wouldn't bother with the ATI's.
As for the Aquablue vs. blue+... the aquablue has a heavy output in the blue as well, with a big curve that gets into the daylight (green) spectrums, but not alot of warmer spectrums. The daylight bulbs are still brighter because warmer spectrums take less energy than cooler ones. T5's may not be as good at making warmer spectrums as halides, but that doesn't mean they aren't still easier to produce than blue, or actinic. The blue phosphors can only go so far though.
Oddly enough, I would challenge those with PAR meters to test their aquablues vs. their blue+ bulbs after 6-9 months... I found on my G-mans (aquablue and actinic+) that the aquablues diminished a bunch in this time, and the actnic+ bulbs held on... their PAR levels were identical.
stony_corals
New member
It's a dual spiked graph, one in red and one in violet/blue range.
Todd March
Premium Member
Yeah, that much is pretty much known. But at what nanometers does it actually specifically spike? And it's obviously got at least a little daylight action going, you can see this with the naked eye, so what other parts of the spectrum does the FJP hit...?
